Front-head construction for self-rotating hammer-drills.



L. (LBAYLES.

APPLICATION FILED JUNE 1-, 1 914v Patented Feb. 2, 915.

FRONT HEAD CONLTRUCTION FOR SELF ROTATING HAMMER DRILLS.

WITNESSES:

BAYLE$L GE WA-WIQN, PENNSYLVANIA, ASSIGNOE T; INGERSOLL-RAND GQHPAN'TE',Q1? JERSEY CITY, NEW JERSEY. A CORPORATION OF NEW JERSEY.

EEUhTT-HEAD CGNSTRUCTION FOR SELF-ROTATING, HAMMER-DBILLS.

i alas-sci Specification of Letters Patent.

Patented Feb. 2, 1915.

a lication, mm June 1, 1914. Serial No. 2,149,

To all whom it may concern.-

Be it known that l, LEWIS C. BAYLES. a citizen of the United States,residing at Eastoinin the county of Northampton and 5 State ofPennsylvania, have invented a certain new andv useful improvement inFront- Head Construction for Self-Rotating Ham- :ner-Drills, of whichthe following is a specification.

This invention relates to self rotating hammer drills, and moreparticularly to a front head construction for drills oi this type foruse in stoping or other drilling where it is necessary to drill verticalholes in the, roof of a stops or entry.

The object of this invention is to provide a front head construction,for drills of this type which will prevent'dust IOm the hole frompenetrating into the moving parts if he drill when it is usedin'vertical or 4, I o 1 n 1 vertical dialling.

olijecbiniiew, a front head cates a piston themovement of whichisgoverned by any desired form of valve mechanism, (not shown}.

The piston is given a step by step rotation by means of a fluted riflebar 5, provided with the ordinary ratchet mechanism 6, this rifle bar '5sliding inn bore 7 in the head of the piston provided with grooves whichare engaged by the flutes on the rifle bar 5. On the forward end of thepistonis a. hammer bar extcnsi on 8 which is provided with straightflutes 9. Fitting into the forward end of the cylinder 8 is a cylinderhead 10. In the rearward part of the cylinder h -d 10 is a bore 11through which the hammer oar extension projects. Forward of this is alarger bore 12. Forward of the cylinder head 10 is a front head 13,which is secured by bolts 15 to'thc cylinder 3, which is also providedwith lugs 16 through which the bolts 14 pass.

14 passing through lug the rearward portion 17 of a drill chuck 18. Therear end of this chuck is provided with a flange 19 which fits in thebore 12. The front, head 13 is also provided with a rear extension 20which also fits into the bore 12 and engages the forward face 21 of theflange The ortion 17 of the drill chuck is bored out receive the hammerar extension of the. piston and is also provided on'its inner surfacewith grooves engaging the straight flutes 9 of the ha mer bar extension.The ohucl'. .1.8 extends no .nd the fron cylinder head :11 a thisforward portion is of no greater diameter than the from rylinder headbore, so that the chuck can be inserted through the rear of the fronthead. The

, iorward portion of the chuck 18 is surrounded by a projecting ring 22which overlaps, the front end of the front head 13 and prevents any dustfalling on the front of the drill from entering the drill cylinder atthe oints between these parts. The ring 22 is secured to the chuck 18 bya key 23, in key way 24. A guard spring 25 is provided to prevent the kefrom becoming displaced.

The forwar portion of the chuck is bored out from its front end toreceive the head portion 26 of a tappet 27 the shank 28 of whichproJects through a smaller bore into the interior of the shank portion17 of the chuck so that it is struck by the hammer bar extension 8 ofthe piston 4. Threaded into the forward portion of the chuck '18 is anose r icce'29 through which is an angular longitudinal aperture 30 jorthe reception of the drill steel, (not shown).

' The operatlon of the device is as follows:

The rotary movement of the piston caused struction the dust falling fromthe hole works down into the moving parts of the drill; quicklyresulting in destructive Wear of the drill. In the between the chuck anfront head is entirely povered by the protecting ring 22. By thisIheans, and also by the rearwardly inclined passages from the tappetbore, dust is entirely prevented from entering the cylinder andafiecting the moving parts.

present form the joint stood thatthc present showing While the chuck ishere shown as rotated by the rotary movement of the piston,conimunicated to the chuck bythe fluted for ward extension of thepiston, it is obvious that other means may he employedwithout inventionfor lircctl or indirectly rotating the chuck, and it is therefore to beunderand desicrin tion discloses only one specified modification of myinvention, and other forms and modifications are included in the spiritand scope of the invention as expressed in the claims.

What Iclaiin is 1. In a fluid operated percussive drill, a cylinder, afront head secured to said cylinder,"said front head having ahbore therethrough, a drill bit receiving chuck rotatahlv mounted in said fronthead, said chuck having a flange on its rear end engaging a rearwarcljliice of saidfronthead, and a for- "\-.'aid portion, of no greaterdiameter than said front head bore, projecting beyond said front head, aring-surrounding said chuck forward portion and overlapping the frontend of said front headInieans for securing said ring to said chuck andmeans for rotating said chuck.

In a fluid operated percussive drill, a

cylinder, a front head having a bore, a piston 111 said cylinder havinga fluted hammer bar :1

extension, a drill chuck rotatably mounted in said front head and havinga front portion projecting therefrom, said chuck having a rearward boreprovided with grooves en a in the flutes of said hammer bar eX- tension.a forward'bore and an intermediate bore of smaller diameter, a tappet insaid forward bore having a shank projecting, into said rearward bore inthe path of said harnnier bar extension, a nose piece threaded intoengaging a rearward face of said front head, 5

a ring surrounding the forward portion of said chuck and overlapping thefront end of said front head, means to secure said ring to said chuckand. means for rotating said piston. In testimony whereof, I havehereunto set my hand.

LEWIS G. BAYLES. Witnesses:

FRED. M. SLATER, ARTHUR SMITH.

